The present invention generically concerns a one-cylinder or two-cylinder hydraulic dashpot for motor vehicles. It comprises a shock-absorber cylinder and a shock-absorber piston and piston rod. The cylinder accommodates a shock-absorbing fluid. The piston divides the cylinder into two displacement compartments. The piston is connected to the vehicle's body or wheel mass by a neck-and-collar pivot that comprises two components. The first component is a collar. The second is a hollow neck. The neck is preferably rubber and metal. The electric supply lines to one or more sensors and/or one or more variable valves extend outward and are connected to the connecting lines of the processing-and/or-actuating circuit by a plug-and-socket connection.
A variable-absorption shock absorber is known from German Patent 2 911 768 C1. The level of absorption is dictated by a bypass in the piston rod. The wires that control the bypass extend through a plug-and-socket connection and into the hollow piston rod. There is an intermediate between the end of the piston rod and a fastener in the form of a neck-and-collar pivot. The intermediate secures the neck-and-collar pivot tight to the piston rod. There is a bore in the intermediate at an angle to the longitudinal axis of the piston rod. The wires that extend from inside the piston rod to the outer surface of the intermediate extend through the bore to a plug-and-socket connection.
There is a drawback to this dashpot. The plug is accommodated in an intermediate below the neck-and-collar pivot. This increases the dead length of the dashpot by the height of the intermediate. It is also difficult to assemble the plug-and-socket connection because the wires leading to the plug must be longer, and the extra length must be accommodated inside the dashpot.
German Patent 3 313 288 C2 describes a variable-absorption dashpot that has the electrical connections for its valves and sensors accommodated in a hollow piston rod and connected by way of a plug-and-socket connection in a cavity in the face of the piston rod with wires leading from a processing and/or actuating circuit. A plug-and-socket connection cannot, however, be accommodated in this position in dashpots that are connected by way of neck-and-collar pivots with the vehicle's body or wheel mass.